Okay, I've seen your leaf gelatin definition and by the taste/smoothness of a superlative cream dessert in England recently, I'm sold! The B&B hostess gave me the recipe happily, but did say the results were superior with leaf gelatin. Where, oh where, can I purchase leaf gelatin in the States?

Sheet or leaf gelatin is not easy to find. We have come across it in an occasional gourmet store or cake decorating store, but even there, it's pretty spotty. Your may find it most consistently online:
Amazon.com and
King Arthur Flour are two sites that offer it. If you need to look further, try searching for both "sheet" and "leaf" gelatin, since either name may show up.

We are not convinced, however, of any wondrous benefit of using sheet gelatin. It has less surface area than granulated gelatin, so it introduces marginally less air into whatever you are making (this can apparently be useful when making a very clear jelly), but beyond that, we don't know of any taste or smoothness gain to be found by choosing it over the much easier-to-find granulated gelatin. Could it be that your B&B hostess was simply an excellent, but slightly imaginative, cook?